Plant Renown German Bearded Iris in well-draining soil with full sun exposure for optimal growth. Water regularly during the growing season, but ensure the rhizomes are not sitting in waterlogged soil to prevent rot. After blooming, remove spent flowers to encourage healthy growth and prevent seed formation. In late summer, trim back foliage to about 6 inches to prepare for winter dormancy. Divide clumps every 3-4 years to maintain vigor and promote flowering.